Identifying Nerves and Blood Vessels

The correct answer is 5 roots. They are roots C5-C8 and T1.

The phrenic nerve is the innervation for the diaphragm. It originates in the cervical spine at the levels of C3-C5. There are two phrenic nerves (left and right), which innervate their respective sides of the diaphragm. A helpful phrase to remember this is "C3,C4,C5 keeps the diaphragm alive!"

The correct answer is the oculomotor nerve. In this case we are looking for a motor nerve that has something to do with the eye, letting us rule out both the olfactory (sensory) and facial (sensory and motor, but not of the eye) nerves. That leaves the oculomotor and optic nerves, however the optic nerve is solely sensory while the oculomotor nerve is a motor nerve.

Of these muscles, the obturator externus is the only one innervated by the obturator nerve. Also, the adductor magnus is innervated by the posterior fibers of the obturator nerve. The obturator internus is innervated by the nerve to the obturator internus. The other deep lateral rotators are innervated by nerves named after the muscles they innervate (e.g. nerve to the piriformis).

The celiac trunk is a major branch of the abdominal aorta. The celiac trunk has three main branches (each of which has its own branches), which include: the left gastric artery, the common hepatic artery, and the splenic artery.

The splenic artery provides blood supply to the spleen. The colon is supplied by the superior mesenteric, inferior mesenteric, and the iliac arteries (the superior and inferior mesenteric arteries are other major branches off the abdominal aorta). The appendix is supplied by the appendicular artery, and the jejunum is supplied by the superior mesenteric artery.

The aorta traverses the diaphragm at level T12. Other structures that traverse the diaphragm are the esophagus, the vagus nerve, the azygos vein, the thoracic duct and the inferior vena cava. The axillary, femoral, pulmonary and common carotid arteries are branches of the aorta, but they do not cross the diaphragm.

The posterior cord of the brachial plexus gives rise to the nerves in the deep compartment of the upper arm. Those are the radial and axillary nerves. The musculocutaneous nerve comes from the lateral cord. The median nerve comes from the lateral and medial cords. The ulnar nerve comes from the medial cord.

The lateral compartment of the leg contains the fibularis longus and fibularis brevis. The muscles of the lateral compartment of the leg are responsible for eversion of the foot and weak plantarflexion of the ankle. The fibularis longus and fibularis brevis are innervated by the superficial fibular nerve (nerve roots L5, S1, S2). The arterial supply consists of perforating branches of the posterior tibial artery and the fibular artery. The great saphenous vein drains, not supplies various compartments of the leg.

There is no maxillary branch of the facial nerve. The branches of the facial nerve are as follows: temporal, zygomatic, buccal, mandibular, cervical, posterior auricular. Recall that the facial nerve is also known as cranial nerve VII.

The palmar digital branches of the median nerve are responsible for cutaneous innervation of the palmar side of the thumb, index finger, middle finger and half of the ring finger.

The superficial branch of the ulnar nerve innervates the palmaris brevis, while the deep branch of the ulnar nerve innervates the third and fourth lumbricals. The radial nerve innervates several structures including the biceps and triceps brachii.